The Taco "Plus One" Multi-Purpose Valve is designed to add one more
feature in every area of the valve’s construction and provide you with
more reliable flow control.
The "Plus One" is not only a check, plug and balance valve—You can also
use it to meter the flow. Two Shrader valve metering connections are
included as standard with each valve. Internally, the valve includes a
bronze gland and stainless steel stem sleeve to give you a lifetime
seal and assure ease of operation after it has been in the line for a
period of time. It won’t freeze up and render itself useless for future
adjustments as cast iron pump discharge valves tend to do.

Taco has also built in easy servicing, if it’s ever needed. You don’t
ever have to concern yourself with stem packing adjustments. A dual
O-ring seal provides leak proof reliability. The gland is removable to
replace O-rings if necessary and an O-ring seal is also provided o the
seat and can be replaced without removing the valve from the line. In
addition, you can easily remove the spherical brass clapper from
the valve.